On Mon, Jul 18, 2022 at 10:53:06AM +0200, Johan Hovold wrote: > From 82faf260d13c9f01e4af664f31231e5d88d7e4f1 Mon Sep 17 00:00:00 2001 > From: Johan Hovold <johan@xxxxxxxxxx> > Date: Mon, 18 Jul 2022 10:21:41 +0200 > Subject: [PATCH] USB: serial: ch341: fix disabled tx timer on older devices > > At least one older CH341 appears to have the TX timer enable bit > inverted so that setting it disables the TX timer and prevents the FIFO > from emptying until it is full. > > Only set the TX timer enable bit for devices with version newer than > 0x27. > > Also try restoring an older init command before updating the line > settings to see if it has any effect on a lost first byte after > initialisation. > > Reported-by: Jonathan Woithe <jwoithe@xxxxxxxxxx> > Link: https://lore.kernel.org/r/Ys1iPTfiZRWj2gXs@xxxxxxxxxxxxxxxxxxx > Not-Signed-off-yet-by: Johan Hovold <johan@xxxxxxxxxx> s/TX/RX/ ... Johan
